Abstract

Amazonian landscapes are associated with the evergreen and exuberant rainforest, the largest river on the planet and a great biodiversity richness. The distribution and physiographic structure of these landscapes result from a continuous multiscale integration of natural systems over geological time. These landscapes occur both on cratonic terrains, deeply marked by past orogenic cycles, and on recent sedimentary sites from the extensive deposition in the central and western parts of the region. The equatorial position of the region since the Miocene ensured elevated temperatures and rainfalls, favoring forest cover and intense weathering. The current climate, however, is marked by a significant seasonality and an uneven distribution of rainfalls. Regional soils are products of long periods of weathering, predominating thick and nutrient-poor Ferralsols and Acrisols. Residual ferricretes support the highest topographic surfaces. The hydrography is organized in a complex system of rivers with waters of different colors—white, black and clear—converging to the Amazon River. This is the river with the largest discharge on the planet, with an annual average of 210,000 m3/s. The dominant vegetation cover is the exuberant rainforest, which contrasts, however, with open formations, locally determined by geological, edaphic and hydrological characteristics. The Amazonia has the largest indigenous population in Brazil and has been colonized since the sixteenth century. Colonization was dispersed and of negligible impact until the middle of the twentieth century, occurring along the fluvial axes. This has been changing in recent decades through the expansion of monoculture for food and energy production. Currently, 43.9% of its surface are Conservation Units and Indigenous Lands. The role of forests as a global climate regulator and as an ethno-cultural heritage is recognized worldwide. Despite this importance, its geological and paleo-environmental history, the structure and functioning of its ecosystems, its natural resources and the fragility of its environments remain little known.

Latrubesse EM, Rancy A (2000) Neotectonic influence on tropical rivers of Southwestern Amazon during the late Quaternary: the Moa and Ipixuna river basins, Brazil. Quat Int 72:67–72CrossRefGoogle Scholar

Leturcq G (2016) Differences and similarities in impacts of hydroeletric dams between North and South of Brazil. Ambiente Soc 19(2):265–286CrossRefGoogle Scholar

Sioli H (1984) The Amazon and its main affluents: hydrography, morphology of the river courses and river types. In: Sioli H (ed) The Amazon. Limnology and landscape ecology of a mighty Tropical River and its basin. Dr. W. Junk Publishers, Dordrecht, pp 127–165Google Scholar